Servo pressure regulator valve



March 18, 1958 J. MERCIER 2,827,075

SERVO PRESSURE REGULATOR VALVE Original Filed Oct. 50, 1944 INVENTORJEAN ME F? 0/5 R BY fat/M414 701M ATTORNEYS United States Patent SERVOPRESSURE BEGULATQF. VALVE Jean Mercier, New York, N. Y.

()riginal application October 30, 1944, Serial bio. 560,998. Divided andthis application September 20, 1951, Serial No. 247,406

4 Claims. ((11. 137-491) My invention relates to unloader valves forservo-pressure regulators, and more particularly to servo-pressureregulators and pressure relief valves in which the position of the mainvalve is controlled by the pressure prevailing inside a pilot pressureroom controlled by a pilot valve.

This application is a division of my copending application, Serial#560,998 filed October 30, 1944 now Patent No. 2,571,154.

One object of the invention is to provide servo-pressure regulators ofhigh sensitiveness, which open and close exactly at the desiredpredetermined pressure.

A particular object of the invention is to produce unloader valves whichopen and close with great precision under elimination of all mechanicalfriction.

Another object of the invention is to produce unloader valves which areoperated exclusively by the pressure in the supply line but which arecontrolled by the pressure in the utilization line so that while themain valve and the pilot valve are opened and kept open, the pressure inthe utilization line may remain unchanged at its maximum value, thuspermitting the omission of the hydraulic accumulator, if desired.

I accomplish this and other objects which will appear more clearly asthe specification proceeds, by the arrangement and combination of partsand elements set forth in the following detailed description, defined inthe appended claims and illustratively exemplified in the accompanyingdrawings, in which the single figure is a sectional view of a pressurerelief valve according to the invention.

Referring now to the drawings, Fig. 1 shows a relief valve in which thecasing 90 is provided with supply ports 92 and return ports 94. The mainvalve means include the valve seat 96, the main valve body 98 with theplunger portion 98 carrying a seal 99, and the plunger chamber 100. Ashort axial tubular passage 192 leads from the plunger chamber 1110 tothe pilot valve seat 102 The pilot valve 112 is pressed against its seatby means of a plunger 108 loaded by a spring 119. The valve body 93 isprovided with an axial bore 103 and an elongated rod 104 passes slidablythrough the bore 103 and with some clearance through the passage 102,and rests with its lower end on the pilot valve 112. A spiral groove 103in the inner wall of the bore 103 provided in the valve body 98 permitsthe leakage of pressure fluid from the inlet port 92 past the rod 104into the plunger chamber 100, which latter forms in this case togetherwith the short passage 102, the pilot pressure room.

In operation, the pressure fiuid passes through the groove 103*- intochamber 190 and keeps the valve body 98 in closed position until thepressure exceeds the predetermined limit. When this limit has beenreached the spring 110 yields, ball 112 moves downward, and the chamber100 is exhausted, permitting the pressure in ports 92 to displace thevalve body 98 into the open position. However, as long as the pressurein the inlet port 92 has not fallen below the predetermined limit, thedrop of ice pressure in the plunger chamber 109 caused by the opening ofthe pilot valve 112 does not permit the latter to return to its closedposition because the inlet pressure acting on the upper end of rod 104is transmitted to the spring 110 to keep the pilot valve open.

As many changes could be made in the above construction and many widelydifierent embodiments of this invention could be made without departingfrom the scope of the claims, it is intended that all matter containedin the above description or shown in the accompanying drawings shall beinterpreted as illustrative and not in a limiting sense.

What I claim is:

1. A pressure regulator valve comprising a casing having an inlet portand an exhaust port with a passageway therebetween defining a valveseat, a main valve having a valve body and having a surface exposed tothe pressure in said inlet port, means resiliently urging said valvebody against said seat to seal said passageway, a pressure charnber insaid casing longitudinally aligned with said valve body, the opposedsurface of said valve body forming one wall of said pressure chamber,said pressure chamber having a discharge passageway therethroughdefining a second valve seat, a ball seated on said seat, meansresiliently retaining said ball in seated position, a bore through saidvalve body into said pressure chamber, a plunger slidably mounted insaid bore and coacting with said ball valve, said plunger and the wallof said bore being conformed for flow of fluid therebetween, wherebywhen said valve is positioned in an inlet line with said plunger insubstantially vertical position beneath said line and the pressure insaid inlet line exceeds a predetermined amount, said ball valve willmove off its seat for flow of fluid through said exhaust port and onlywhen the pressure in said inlet port has fallen below said predeterminedamount will said second resilient means again seat said ball valve tocut off communication between said inlet port and said exhaust port.

2. The combination recited in claim 1 in which the outer end of saidplunger in said bore is exposed to the pressure of the fluid in saidinlet port.

3. The combination recited in claim 1 in which said casing has asubstantially cylindrical sleeve therein, said valve member is slidablymounted in one end of said sleeve, a plug in said sleeve between theinner end of said valve member and the other end of said sleeve definesthe pressure chamber, said sleeve having a passageway thereinto betweenthe plug and the other end of the sleeve providing communication fromsaid sleeve to said exhaust port.

4. The combination recited in claim 3 in which said first resilientmeans comprises a coil spring compressed between the inner end of thevalve member and the plug, a second plunger having a collar thereonreacts against said ball valve, an end plug seals the other end of saidsleeve and said second resilient means comprises a second coil springcompressed between said end plug and said collar.

References Cited in the file of this patent UNlTED STATES PATENTS534,514 Mellin Feb. 19, 1895 934,083 Mills Sept. 14, 1909 2,069,522Flournoy Feb. 2, 1937 2,091,596 Kluppel Aug. 31, 1937 2,366,596 CliftonJan. 2, 1945 2,404,102 Schultz July 16, 1946 2,410,751 Schultz Nov. 5,1946 2,447,820 Schultz Aug. 24, 1948 2,479,359 Holt Aug. 16, 19492,487,575 Mercier Nov. 8, 1949 2,571,154 Mercier Oct. 16, 1951

